[racket] Setting up Scribble documentation in a .plt archive

We're trying to create .plt archive for distribution, along with
documentation for the software.  Currently, when I install the plt
file from the menu in DrRacket, it installs the software successfully,
but seems to skip the documentation.  The output looks like this:

setup-plt: --- compiling collections ---
setup-plt: making: <user>/class0 (class0)
 .. lots of appropriate output here ..
setup-plt: --- updating info-domain tables ---
setup-plt: updating: <user>/info-domain/compiled/cache.rktd
setup-plt: --- creating launchers ---
setup-plt: --- building documentation ---
setup-plt: --- installing collections ---
setup-plt: --- post-installing collections ---
setup-plt: done

Note that nothing happens in the "building documentation" step.
What's the right incantation for getting the documentation generated?
The .plt file is generated with:
  raco pack ++setup class0 --at-plt --replace class0.plt class0/

If I then do 'raco setup class0' at the command line (not an option
for the intended audience), I get this:

raco setup: --- building documentation ---
raco setup: running: <user>/class0/scribblings/class0.scrbl
raco setup: skipping: scribblings/main/user/start.scrbl
raco setup: skipping: scribblings/main/user/search.scrbl
raco setup: rendering: <user>/class0/scribblings/class0.scrbl

Note the "skipping" lines, which means that our new documentation is
not indexed.  I don't know why this happens either.

If I then run a *full* 'raco setup', the documentation is finally indexed.

This is all for 5.0.2.
-- 
sam th
samth at ccs.neu.edu